A conventional down-conversion mixer proposed in an article by Ning Zhang et al., entitled “W-Band Active Down-Conversion Mixer in Bulk CMOS,” in IEEE Microwave and Wireless Components Letters, vol. 19, no. 2, pp. 98-100, February 2009, operates in a 76 GHz-77 GHz frequency band, and has a conversion gain of −8 dB and a noise figure of 17.8 dB.
Another conventional down-conversion mixer proposed in an article by Yo-Sheng Lin et al., entitled “A W-Band Down-Conversion Mixer in 90 nm CMOS with Excellent Matching and Port-to-Port Isolation for Automotive Radars,” in 2014 11th International Symposium on Wireless Communications Systems, pp. 54-58, August 2014, operates in a 75 GHz-85 GHz frequency band, and has a conversion gain of 1.5 dB and a noise figure of 23.3 dB.
Measurement results of the above-mentioned conventional down-conversion mixers are shown in Table 1 below. It is known from Table 1 that each conventional down-conversion mixer is unable to simultaneously achieve high conversion gain and low noise figure.
TABLE 1Down-ConversionDown-ConversionMixer byMixer byNing ZhangYo-Sheng Linfrequency of radio7677frequency input(GHz)frequency of60.1intermediatefrequency output(GHz)conversion gain (dB)−81.5noise figure (dB)17.823.3input third-order2.52.7intercept point(dBm)size (mm2)0.42—